Costa Rica has had, for 25 years, its very own ambassador to space in astronaut Franklin Chang.
Now, plans are in motion for Chang’s biggest idea to be launched into space. Chang’s Webster, Texas-based Ad Astra Rocket Co. last week signed a contract to make use of its plasma-propulsion rocket system, presently in development, with the U.S. National Aeronautics and Space Administration (NASA).
Plasma is the fourth state of matter – besides solid, liquid and gas – and the universe’s most common. Lightning, nebulae, the sun and the stars are all examples. “Think of plasma as a super-heated gas,” Tim Glover, Ad Astra’s director of development told The Tico Times. “It’s been stripped of its electrons and carries a positive electrical charge.”
Glover added that physics’ use of the term “plasma” has nothing to do with the more well-known plasma, a component of blood.
Rocket propulsion is based on the principle of expelling exhaust material at high velocity, thereby driving the vehicle in the opposite direction. Plasma can eject exhaust 20 times faster than conventional chemical materials, Glover explained. Achieving the same effect requires 20 times less material.
“More cost effective,” he added. “It’s less fuel the rocket needs to haul.”
Chang, 58, a veteran of seven NASA space missions and an applied physicist by training, began formulating the concept in 1979. The astronaut, arguably one of the world’s best known Ticos – he holds dual U.S.-Costa Rican citizenship – retired from the space agency in 2005.
The end result of Chang’s dream will be known as the Variable Specific Impulse Magnetoplasma Rocket (VASIMR), with the “magnetoplasma” portion of the name a major key to the solar-powered system’s operation.
Plasma can reach temperatures of 50,000 degrees Celsius, generating heat that would disintegrate conventional rocket material, Glover said. But magnetic fields convert light gases, such as hydrogen, into plasma, passing it through the chambers of the system and expelling it, protecting the rocket construction itself from contact.
With the signing of the Ad Astra-NASA contract, 2012 is now the target date for providing power to a vehicle that can transport material, support and attachments to the International Space Station.
A plasma-propelled system, which requires extremely low, near-vacuum pressures to operate properly, would never actually be involved in a rocket liftoff.
“It will take over once in orbit,” Glover says.
Project development is now at the stage of testing a ground-based prototype known as the VX-200. Flight-like components are undergoing a trial to determine their viability in a vacuum environment at a power of 200 kilowatts.
Once VASIMR is completed, Ad Astra researchers envision the possibility that it could provide a far more efficient means of transport to be used for missions to the moon or Mars.
Ad Astra Costa Rica, the company’s subsidiary based near the northwestern city of Liberia, has been in operation since 2006.
The company also is pioneering methods of converting trash and medical waste into plasma (TT, July 11).
“Both sites are conducting plasma research,” Glover said. “That’s the real common thread between the two.”